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speedometer/transmission/AC problem

Once every few minutes, when I’m driving at a steady speed my car’s speedometer drops to almost zero for less than a second, and then bounces back up. Sometimes it hesitates or clunks, like the transmission (automatic) downshifted momentarily. It only does all of this when the AC is on. I’ve had it to 3 mechanics, a total of 7 times, with no success.

Have they looked into the output speed sensor and its wiring??

transman

My mechanic says he replaced the output speed sensor and checked the wiring from the sensor to the transmission control module (repeatedly). The previous two couldn’t find problems with these either, and the Chrysler tech line couldn’t find any problems with the vehicle either.